#include <iostream>
using namespace std;

int main()
{
    int n, i;
    bool prime = true;

    cout << "Enter a number: ";
    cin >> n;

    if (n <= 1)
        prime = false;
    else
    {
        for (i = 2; i < n; i++)
        {
            if (n % i == 0)
            {
                prime = false;
                break;
            }
        }
    }

    if (prime)
        cout << n << " is a prime number.";
    else
        cout << n << " is not a prime number.";

    return 0;
}